The BatRok was inspired by the Batman TV series which started to air in the 1960's. The fins give it an obvious bat-like look. The model rocket was originally designed by Ron Maggiano, a high-school student at the time. With this design, he won a rocket design competition, sponsored by Centuri Engineering Company. This RetroRepro Batrok rocket has been brought up-to-date by Semroc Astronautics Corporation with laser cut fins, and Kevlar & elastic shock cords. The size of the rocket was not modified. The Semroc RetroRepro series features out of production model rocket kits of historical significance. These kits are not intended to be true clones of the originals, it takes advantage of technology to improve them. In addition to the cool fins, the model also features a clear payload section. The way it looks alone was sufficient to select it for immediate review.

Parts List

The below items are included with the model rocket kit. These will be used to build your very own BatRok rocket.

- 1 body tube, trust ring and launch lug
- 1 clear plastic tube (payload area)
- balsa nose cone, balsa tube coupler and screw eye
- 8 laser cut fins
- black kevlar thread and elastic cord
- 12" plastic parachute kit
- water decals
- empty casing
- assembly instructions, guarantee information, and safety code

Launch supplies are not included. You'll also need hobby tools and supplies such as glue, a hobby knife and so on. No special tools required.

Construction

This is a model rocket kit suited for beginners. It is intended for rocketeers age 10 and up (adult supervision required under 12). The instructions are easy to follow and are accompanied with images for added clarity.

First, the engine block and shock cord are put into place. Next, the fins are prepared and attached. The payload section is put together and once the parachute is added, the model rocket is ready for finishing.

Be sure to read all the instructions and follow them. This rocket actually has the shock cord coming out of the aft end and running along the outside of the airframe tube. Going with the traditional setup, inside the body tube, would cause the upper fins to get tangled up in the parachute's shroud lines.

While this is a different way to do things, it doesn't make building the rocket any more difficult.

Measurements

The BatRok is 12" long (30.5 cm) with a fin span of 4" (12.2 cm). It has a body diameter of 0.759" (1.9 cm) and weighs 0.6 oz (15.9g).

Finishing

The fins were sanded and sealed, as instructed. Next, a coat of Rust-Oleum automotive primer was applied.

The water decals are mostly black. While it is very tempting to paint this rocket black, you won't be able to see the decals if you do so. If you don't plan on using the decals, go ahead and paint this rocket as black as a bat.

The instructions booklet suggests using a dark gray paint. Some Testors Acryl black (#1369) and white (1372) paint were mixed to obtain the gray which was used to paint the BatRoc. The mix was 2/3 white and 1/3 black. Some water was added to make it spray-able.

Flight Data

The engines suggested for use with this Semroc model rocket are : A8-5, B6-6, C6-7.

When launched with a B6 rocket motor, the Batrok goes straight up at first and then veers off slightly to one side. Parachute appears to deploy right around apogee. The rocket was recovered a few hundred feet from the launch pad, due to a 3-5 mph wind. It would probably do very well with a slightly smaller parachute too.

On its first flight, the rocket was recovered without its nose cone. The nose cone will be replaced and the model will be flown again.

Update : The replacement Semroc nose cone has a loose fit. Some masking tape was wrapped around the shoulder to give it a better fit.

As conditions were windy, a spill hole was cut in the parachute. Launched on a B6-4 again, the flight was quite impressive. The parachute deployed and the rocket started down. It managed to land (new nose cone and all) no more than 5-10 feet away from the field in bushes where snakes are bound to live and collect rockets. No recovery was attempted to avoid snakes and other critters.